The present invention relates to a container or bag for supplying detergent or wash solution to the circuits and filters of dialysis equipment.
For dialysis applications, increasing use has been made over the past few years of disposable single-cycle plastic circuits and filters.
This applies in particular to those parts of the dialysis equipment coming into contact with the patient's blood.
Such circuits and filters are made of appropriate plastic material and, prior to use, i.e. before being connected to the patient's circulation system, must be washed using a physiological (e.g. 0.9% NaCl) solution for eliminating even minor traces of substances used in the manufacture, completion and, particularly, sterilization of the circuits and filters (such as glycerine, ethylene oxide, etc.).
This is not only advisable from the therapeutic standpoint--in that even minor traces of such substances may possibly be toxic and at any rate are certainly to be avoided in the case of patients subjected to a blood purifying process--but is also prescribed by specific health regulations.
Italian Patent n. 1-209.560, issued on 30 August, 1989 to Pierrel Hospital Spa and subsequently transferred to the present Applicant, relates to a container for supplying a wash solution to the circuits and filters of dialysis equipment.
The same patent, which forms an integral part of the present description and to which full reference is made herein in the interest of full disclosure, also relates to a special washing method, and to a number of alternative extracorporeal circuits to which the method also applies.
In particular, the above patent relates to a container for performing the above functions, and comprising two side side, independent, noncommunicating chambers connectable to the extracorporeal circuit on the blood side of the dialysis equipment.
A first chamber contains a certain amount of physiological solution which is circulated continuously in the circuit and back to the first chamber.
This provides for a first wash cycle for removing any toxic substances contained in the circuit.
Subsequently, a certain amount of fresh physiological solution is withdrawn from the second chamber and fed into the circuit for the final wash cycle.
At this point, the circuit is ready for connection to the patient.
To prevent the physiological solution from stagnating inside the first chamber, this is provided inside with a partition extending from the base of the container towards the opposite portion, to a point roughly halfway up the chamber, and located between two inlet/drain fittings connected to the circuit, so as to form a compulsory path for the physiological solution circulating in the first chamber.
Though generally successful, the above partition solution fails to provide for eliminating stagnation under certain extreme circumstances (involving, for example, a fairly high content of toxic substances in the circuit, or due to the nature of the toxic substances or the speed at which the physiological solution is circulated inside the chamber).